# operator==,<,>,<=,>=,<=>(ranges::concat_view::iterator)

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< cpp‎ | ranges‎ | concat view‎ | iterator

friend constexpr bool operator== ( const /*iterator*/& x, std::default_sentinel_t ); | (1) | (since C++26)
friend constexpr bool operator== ( const /*iterator*/& x, const /*iterator*/& y ) requires (std::equality_comparable<ranges::iterator_t< std::conditional_t<Const, const Views, Views>>> && ...); | (2) | (since C++26)
friend constexpr bool operator< ( const /*iterator*/& x, const /*iterator*/& y ) requires /*all-random-access*/<Const, Views...>; | (3) | (since C++26)
friend constexpr bool operator> ( const /*iterator*/& x, const /*iterator*/& y ) requires /*all-random-access*/<Const, Views...>; | (4) | (since C++26)
friend constexpr bool operator<= ( const /*iterator*/& x, const /*iterator*/& y ) requires /*all-random-access*/<Const, Views...>; | (5) | (since C++26)
friend constexpr bool operator>= ( const /*iterator*/& x, const /*iterator*/& y ) requires /*all-random-access*/<Const, Views...>; | (6) | (since C++26)
friend constexpr auto operator<=> ( const /*iterator*/& x, const /*iterator*/& y ) requires (/*all-random-access*/<Const, Views...> && (std::three_way_comparable<ranges::iterator_t< std::conditional_t<Const, const Views, Views>>> && ...)); | (7) | (since C++26)

Compares the iterator with another iterator or a sentinel.

1) Compares an iterator with a sentinel.
If x.`it_`﻿.valueless_by_exception() is true, the behavior is undefined.
2-7) Compares two iterators. The `!=` operator is synthesized from `operator==`.
If x.`it_`﻿.valueless_by_exception() || y.`it_`﻿.valueless_by_exception() is true, the behavior is undefined.

These functions are not visible to ordinary unqualified or qualified lookup, and can only be found by argument-dependent lookup when `std::ranges::concat_view::iterator﻿<Const>` is an associated class of the arguments.

### Parameters

x, y | - | iterators to compare

### Return value

1)

x.`it_`﻿.index() == (sizeof...(Views) - 1) &&
`` x.`get-iter`﻿<sizeof...(Views) - 1>() == x.`get-end`﻿<sizeof...(Views) - 1>()

2) x.`it_``` == y.`it_`
3) x.`it_``` < y.`it_`
4) x.`it_``` > y.`it_`
5) x.`it_``` <= y.`it_`
6) x.`it_``` >= y.`it_`
7) x.`it_``` <=> y.`it_`

### Example

| This section is incomplete Reason: no example

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